Although it was in use in China before the advent of the Mongols, the paiza, an inscribed metal plaque that functioned as a passport or a patent of office, became a symbol of Mongol administration used to regulate and secure communication in the vast empire. Most paizi were circular or rectangular and were worn either fastened on an item of clothing or suspended from the neck to make them visible to customs officers. These metal plaques are not only important historical documents but are also of great interest for the study of Asian metalwork during the thirteenth and fourteenth centuries, a time of massive movements of people and rapid exchange of ideas and technology.

Two kinds of Mongol plaques were issuedto officials as patents of office, and as passports for persons on state missions and for important guests. (Marco Polo on his return journey to Venice would have carried one.) The paiza illustrated here is a passport, made of iron with inlay of thick silver bands forming characters in the Phagspa script, devised for the Mongol language in 1269 by the Tibetan monk 'Phagspa (12351280), a close advisor to Kublai Khan (r. 126095). The inscription reads in translation (by Morris Rossabi):

By the strength of Eternal Heaven,an edict of the Emperor [Khan].He who has no respect shall be guilty.

Above it is a lobed handle, with an animal mask in silver inlay. The mask is probably the kirttimukha (lion mask) taken from Tibetan art but ultimately of Indian origin; the lobed shape reflects Islamic influence. Silver inlay on iron (as opposed to bronze) is extremely rare in China before the Mongol period.

This plaque is one of about a dozen Mongol paizi known. Two others of the same type are in Lanzhou, China, and in Russia. (The latter example was found during the nineteenth century in Tomskaya.)